| 摘要:应用FIRE软件,对一种吊钟型涡流室式柴油机的压缩、喷雾过程进行模拟,考察气流运动、喷雾方向对混合气形成、分布、扩散过程的影响。对于喷雾过程,主要通过缸内的燃空当量比分析了燃油的分布情况；由油滴在涡流室内的粒径云图观察喷雾的形态。模拟结果表明:涡流室内强烈的气流运动对燃油的雾化作用很大,由于气流的阻尼作用,油滴不断破碎、雾化、蒸发,最终形成可燃混合气；改变喷雾方向,可以实现燃油的碰撞喷雾,油滴的破碎,使混合气在涡流室内均匀分布,有利于燃油的充分燃烧。 |
| 关键词: 涡流燃烧室 碰撞喷雾 数值模拟 |
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| Numerical Simulation of the Spray Impingement in a Swirl Chamber |
| An Xifang |
| School of Energy and Power Engineering,Dalian University of Technology,LiaoningDalian116024 |
| Abstract:Using AVL FIRE software, the compression and expansion stroke of a diesel engine with bell type swirl chamber is simulated. The influence of the gas flow and injection direction on the mixing and diffusion process is studied. As for injection process, the distribution of fuel in the swirl chamber is analyzed by controlling fuel air equivalence ratio in the chamber. The shape of spray is described with spray cloud in the swirl chamber. The result shows that the strong air movement in swirl chamber has big influence on the atomization of fuel. Because of the damping effect of air flow, oil droplets are broken, atomized, evaporated, then combustion finally become available. The spray impinging in chamber wall will take place when changing injection direction, that improves the broken of oil droplets, and the mixture will be distributed in swirl chamber more evenly, which is preferable for the following combustion. |
| Key words: swirl chamber spray impingement numerical simulation |
